Vent plug



Aprii 17, 1951 A. M. MILEY ETAL 2,548,995

VENT PLUG Filed Feb. 6, 1947 INVENTORS ALBERT M- MILEY JOHN E. WHiTE w Ja 'TTORNEY Patented Apr. 17, 1951 UNITED STATES PATENT OFFICE VENT PLUG of New Jersey Application February 6, 1947, Serial No. 726,890

2 Claims. 1

This invention relates to vent plugs for storage batteries.

An object of the invention is to provide improved vent plugs which are of inexpensive and simplified construction, and yet are particularly eifective in preventing escape of liquid from battery cells.

A further object of the inventionis to provide vent plugs in which improved arrangements of a chamber, communication apertures thereto and baffle means are employed to entrap vapors and splashed electrolyte that escape from battery cells and return such vapors and electrolyte to the cells.

A further object of the invention is to provide improved vent plugs having the foregoing characteristics and constructed of two sections so designed that they may be readily molded and permanently secured together to furnish a unitary plug.

A further object of the invention is to provide improved means for joining vent plug sections to insure that the sections are in proper relation to each other.

In accomplishing these and other objects of the present invention, we have provided improved details of structure, a preferred form of which is shown in the accompanying drawing, wherein:

Figure 1 is a vertical sectional view of a portion of a storage battery cover and a vent plug constructed in accordance with principles of the present invention;

Figure 2 is a perspective view of the upper plug section, viewing it from beneath; and

Figure 3 is a perspective view of the lower plug section, viewing it from above.

Referring more in detail to the drawing and with particular reference to Figure 1, it is seen that the vent plug of the present invention comprises a lower section I and an upper section I l. Sections l0 and H are preferably molded as integral pieces from a suitable plastic material resistant to battery electrolyte, of which many are known, as, for example, hard rubber and various synthetic resins.

Lower section II] includes an annular barrel l2, a. horizontal baflle 13 extending across the barrel adjacent the bottom thereof and a horizontal flange 14 extending outwardly from the circumference of said barrel adjacent the top. The exterior of the barrel is threaded or otherwise provided with fastening means to cooperate with similar fastening means in an opening in a battery cover, designated 15, to secure the vent plug thereto. Baflle 13 contains a vent aperture l6 preferably located near an edge thereof and communicating between the cell interior and the space above said baflle.

Upper section 4 I includes a hollow body I! preferably of dome-shape. The lower diameter of body IT is such as to register with the circumference of flange l4. Said body preferably has gripping means formed thereon, and such means may conveniently include a plurality of wings [8. A vertical baflle I9 is formed in body I1 and extends laterally thereacross, preferably at one side of the horizontal center line of the body. Body I? has a vent aperture 20 communicating between the space beneath said body and the surrounding atmosphere and located on the opposite side of baille l S from the horizontal center line.

It is seen that each section is of a configuration that may be readily molded by use of standard methods and apparatus. There are no portions that interfere with removal of the sections from molding apparatus.

Sections IE3 and l i are secured together at the surfaces at which the circumference of body I! contacts the circumference of flange M. This is preferably accomplished by cementing, but may be accomplished by any suitable mechanical securing means. The sections are joined with the vent apertures l6 and 29 in non-aligned relation,

being preferably in diametrically opposed rela-' tion. Baille I8 is disposed in a plane normal to bafile I 3 and interrupts the direct line of flow between apertures 16 and 20.

Preferably means are provided on the contacting faces of the sections to prevent joining of the sections unless the apertures are in proper relation. In the preferred embodiment such means comprise an arrangement of arcuate keys upstanding from flange M of lower section In and being of the configuration illustrated in Figure 3. Said keys include flanges 2| and 22 upstanding from. the circumferential edge of flange M and flanges 23 and 24 upstanding from flange Id, but spaced inwardly from the circumferential edge. The are of flange 2| is different from that of flange 22, the former being shown as greater than the latter. It is obvious, however, that the arrangement could be reversed or other designs of keys employed without departing from the invention. 1

As shown in Figure 2, the lower edge of upper section H has complementary key portions designed to mate with those of the lower section.

The key means interfit only when the sections are arranged with the baffles and vent apertures in proper relation and they must interfit before the sections can be secured together. Thus th key means insure that the sections are in proper relation when they are joined.

When the sections are joined as described, they define a chamber, designated 25. Gases evolved from the battery electrolyte enter chamber 25 through aperture I6 and escape therefrom through aperture 28, the bafiie means and the constrictions at the apertures not appreciably interfering with passage of such gases.

When electrolyte splashes from the cell due to vibration or other causes, a small amount may enter chamber 25 through aperture :6. However, baille i9 prevents direct escape of splashed electrolyte through aperture 29. Some water also evaporates from the electrolyte, and a portion of the vapor are entrapped or condensed as they flow around said baffie. Likewise liquid may be condensed or entrapped on the under surface of the dome of body ll. Baffle l9 prevents such liquid from creeping along said under surface to aperture 20 where it might be forced from the chamher by escaping gas. splashed electrolyte and condensate, being prevented from escaping through aperture 2E, eventually return to the cell through aperture Hi.

Thus it is seen that we have provided improved vent caps of two parts joined to form a unitary construction and particularly efiective in preventing loss of liquid from battery cells.

While we have shown but a single embodiment of the present invention, it is apparent that modifications may arise. Therefore We do not wish to be limited by the disclosure set forth, but only by the scope of the appended claims.

We claim:

1. A storage battery vent plug comprising lower and upper molded sections rigidly joined to form a unitary structure and defining a chamber, said lower section including an annular barrel, means on said barrel adapted to secure the vent plug in a battery well, an outwardly extending circumferential flange adjacent the edge of said barrel to which said upper section is joined, key means on said flange, and a baflle of circular outline across said barrel having an aperture adjacent an edge adapted to furnish communication between said chamber and the interior of a battery cell, said upper section including a body of dome shape having an aperture adjacent an edge remote from said first aperture adapted to furnish communication between said chamber and the surrounding atmosphere, a baffle disposed in a plane normal to said first bafiieinterrupting the direct line of fiow between said apertures, and means on the circumferential edge of said body cooperable with said key means to insure that said apertures are in proper relation when said sections are joined.

2. A storage battery vent plug, comprising lower and upper molded sections rigidly joined to form a unitary structure and defining a chamber, said lower section including an annular barrel, means on said barrel adapted to secure the vent plug in a battery well, an outwardly extending circumierential flange adjacent the edge of said barrel to which said upper section is joined, a plurality of flanges upstanding from said circumferential flange and cooperating with similar depending flanges on the lower portion of said upper section to insure correct alignment of said upper and lower sections, a battle plate across said barrel having an aperture adjacent an edge thereof, said upper section including a dome shaped body having an aperture therein remote from said first aperture, and battle means depending from said dome and interposed said apertures.

ALBERT MILTON MILEY. JOHN EDWARD WHITE.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name 1 Date 1,010,695 Sloan Dec. 5, 1911 1,613,955 Lesley Jan. 11, 1927 1,999,952 Amidon Apr. 30, 1935 2,061,649 Campbell Nov. 24, 1936 FOREIGN PATENTS Number Country Date 546,943 Great Britain Aug. 6, 1942 

